1. Introduction
Understanding dietary exposures during different life stages is particularly important among infants and toddlers. Infancy and early childhood are critical periods for the development of taste preferences and dietary patterns [
1,
2,
3]. In addition, early dietary behaviors lay the foundation for future dietary patterns with the potential to prevent diet-related chronic disease in later life [
4,
5,
6]. Understanding how infant and young children’s intake aligns with current dietary guidance is of public health importance. Knowledge of trends in dietary intake patterns of infants and young children in the United States can inform policy and programmatic efforts to improve infant and child health. Yet data on patterns of food and beverage intake are limited for this age group.
Two studies, each using data from the National Health and Nutrition Examination Survey (NHANES), examined trends in food and beverage intake in this age group [
7,
8]. However, these studies lack recent data and there is limited understanding of population-level changes in food consumption behaviors of young children over time [
8]. A more recent analysis using data from the Feeding Infants and Toddlers Study (FITS) examined trends in nutrient intakes among 0–47.9-month-olds and found that nutrient intakes were generally stable from 2002 to 2016; however, sodium intakes exceed recommended levels and there were notable declines in vitamins D and E and fiber among the entire sample and in iron among infants [
9].
It is important to examine trends in food consumption alongside trends in nutrient intakes to understand how food consumption behavior may be contributing to observed changes in nutrient intakes. Given the gaps in the literature, the aim of this study is to assess trends in food and beverage consumption (per capita and per consumer) among children ages 6–23.9 months from the FITS conducted in 2002, 2008, and 2016. This study provides the most recent information on young children’s dietary intake and how intake has changed across three time periods in the past 15 years. This information can inform policy, program, practice, and intervention efforts aimed at improving the diets and overall health of infants and young children in the United States.
4. Discussion
Using cross-sectional data from three different FITS (2002, 2008, and 2016), we identified some positive shifts in the diets of infants and young children in the United States, including increases in breastfeeding prevalence and decreases in consumption of 100% juice, sweets, SSBs, and desserts; but we also identified concerning trends such as decreases in the percent of infants consuming whole grains and stagnation in vegetable intake. Our results can be used to guide the efforts of health care providers, public health practitioners, researchers, and policymakers to improve the diets and overall health of infants and young children.
A key finding was the increase in prevalence of breast milk consumption among 6–11.9-month-olds over the three survey years. Breastfeeding is recommended by the American Academy of Pediatrics (AAP) until 1 year of age and longer if mutually desired by the mother and the infant [
20]. A recent trend analysis of NHANES 2005–2008 and 2009–2012 data found no changes over time in the percent of 6–12-month-olds breastfeeding [
7]. However, another NHANES analysis encompassing a longer time period compared 1997–2000 and 2009–2012 breastfeeding prevalence and found the percent of children still breastfeeding at 6 months increased significantly from 36% to 43% [
21]. Several secular trends may explain the observed increase in breastfeeding prevalence. These include changes in WIC policies and programs, including implementation of a breastfeeding peer counseling support program in 2004 and revisions to the WIC food package in 2009 to better support breastfeeding. WIC is a federal nutrition assistance program for low-income pregnant, post-partum, and breastfeeding women, infants, and children up to age 5 that provides nutritious foods, nutrition education, breastfeeding support and health care referrals. Other trends that may have contributed to increases in breastfeeding prevalence include increases in the number of baby friendly hospitals; improved workplace support for breastfeeding mothers; increased insurance coverage for breast pumps; and decreases in infant formula advertising spending [
22,
23,
24]. While these are promising trends, future efforts should emphasize ensuring that these positive changes are realized equally among all sociodemographic groups.
There were few shifts in consumption of cow’s milk or other dairy products. A concern noted across all survey years was that approximately 10% of 6–11.9-month-olds were consuming cow’s milk, which is not recommended by the AAP or other expert groups until 1 year of age [
20,
25]. We observed a significant increase in yogurt consumption among 12–24.9-month-olds. Although evidence suggests yogurt can contribute key nutrients, like calcium, to children’s intake, products vary widely in sugar content, and yogurt positioned for consumption by children may be higher in added sugars [
26,
27].
Over the last decade, there has been notable reformulation of grain-based products to increase whole grain content; labeling of whole grain foods has also improved in that time frame. Despite that, we observed declines in the percentage of 6–11.9-month-olds consuming whole grains, and in the amount consumed per capita. There was no change in the percent of 12–23.9-month-olds consuming whole grains, but an increase in the amount of whole grains consumed, perhaps due to reformulation. Studies using NHANES data to examine trends in the amounts of whole grains consumed among older children and adolescents have found mixed results, with intake either improving or staying the same over time [
28,
29,
30]. There is still a notable percentage of infants and young children who did not consume whole grains on the day of the survey. This should be a focus of future policy and programmatic efforts because whole grains are an important source of fiber, which is an under-consumed nutrient among young children in the United States [
31].
Among 6–11.9-month-olds, there was a decrease in the consumption of infant cereal over the three survey years. Iron-fortified infant foods can be a key source of much-needed iron during this life stage, and about 20% of 6–11.9-month-olds are at risk of inadequate iron intake [
31,
32]. Data from the FITS 2016 suggest that infant cereal and meats are some of the most commonly consumed complementary foods among 6–11.9-month-olds, behind fruits and vegetables [
33]. Moreover, some FITS data indicate that the types of meats consumed are usually poultry or cold-cuts, which often contain less bioavailable sources of iron than beef [
34]. However, in 2013, the AAP released guidance for parents to offer a wide variety of foods to decrease exposure to arsenic in rice and rice products in response to a U.S. Food and Drug Administration (FDA) risk assessment. The FDA recommended to continue to feed infant cereal made from other grain sources [
35]. This guidance and the FDA risk assessment may have contributed to declines in consumption. If the decline of infant cereal, a key source of iron for infants, is not replaced with other bioavailable sources of iron in the diet, lower consumption of infant cereal could contribute to inadequate iron intakes. Efforts should be made to help parents and caregivers understand the importance of adequate iron consumption in infancy and appropriate sources of iron, such as infant cereals made from oats, wheat, and barley, as well as meats.
There was no significant change in the percent of children consuming any distinct portion of vegetables or the amount of any distinct portion of vegetables consumed over the three time points. Still, about one in four children from 6–23.9 months are not consuming any vegetables on a given day. There was a slight increase among 6–11.9-month-olds in consumption of non-baby food vegetables, perhaps attributable to the rise of the baby-led weaning infant feeding style, which encourages self-feeding of family foods in whole form [
36]. Establishing preferences for vegetables early in life is critical for continued consumption throughout early childhood [
2,
37]. Similar to our findings, a trend analysis of NHANES data from 2003–2010 found no changes in vegetable intake for children 2–18 years old, with no children meeting the Healthy People 2020 vegetable intake targets [
38]. Vegetables are a critical source of fiber, vitamins, and minerals throughout life [
30]. Infants may initially reject vegetables due to their relatively bitter taste profile; however, there are many strategies that parents and caregivers can employ, such as repeated exposure, pairing vegetables with liked foods, and modeling healthy eating, that can improve acceptability and consumption. In addition to these individual-level strategies, approaches at all levels of the socioecological model are drastically needed to improve vegetable intake in infancy and early childhood [
39].
We found declines in the percent of children consuming 100% fruit juice and the amount of 100% fruit juice consumed. The AAP recommends that no 100% fruit juice be consumed prior to 1 year and that 1–3 year olds should consume whole fruit if possible, but if not, a maximum of 4 ounces of 100% fruit juice per day is recommended to meet fruit intake recommendations [
40]. These AAP recommendations were released in 2017, so were not a contributor to the observed declines. However, prior to these recommendations, there was some evidence suggesting that 100% fruit juice intake in early childhood may contribute to excess energy intake, increased risk of dental caries, and a heightened preference for sweet foods and beverages [
41,
42,
43]. Additionally, in 2009, the WIC food package was updated, no longer allowing 100% fruit juice purchases for infants and reducing the amount of 100% fruit juice included for 1–5-year-old children. Approximately 30% of the FITS sample participated in WIC at the time of the survey, so it is plausible these policy changes impacted intake. Similar declines in 100% fruit juice among this age group have been observed in other studies [
7,
44]. There were no significant shifts in whole fruit consumption across survey years. Our findings differ from an analysis of NHANES data from children ages 2 to 18 that found increases in whole fruit consumption between 2003 and 2010 [
38].
Unlike fruits, vegetables, and whole grains, most children in the age groups included in this study meet the intake recommendations for total protein [
25,
31,
45]. We observed increases in protein consumption over the three surveys. The increase in non-meat protein consumption found among 12–23.9-month-olds is important, as some varieties of meat can be a key source of essential micronutrients such as B12 and bioavailable iron. Similar increases in non-meat protein sources in this age group have not been observed in trend analyses of NHANES data; however, those analyses include data only up to 2012 [
7].
The trends we observed in consumption of sweets and SSBs are encouraging. Yet, there are still many infants and young children consuming these foods and beverages despite recommendations that no added sugar should be consumed prior to 2 years [
25,
46]. In trend analyses using NHANES data among this age group, similar declines have been observed in sweet and dessert consumption, but not in SSB consumption. In older age groups (2 to 18 years), NHANES data shows similar declines in SSB consumption over time [
47]. The most commonly consumed variety of SSB in this age group was fruit flavored drinks at all three time points, making these beverages an important target for future intervention efforts.
A key limitation of this study is the use of parent or caregiver reported intake, which is inherently impacted by measurement error and some degree of reporting bias. Additionally, we did not have sufficient sample size to examine differences in trends by racial/ethnic group. This will be an important area to examine in future research to understand if observed improvements in dietary intake are realized equally among all infants and toddlers. There were many strengths to this study. This is, to our knowledge, the most comprehensive evaluation of trends in dietary intake in this age group. The FITS is one of the largest national studies that examines the dietary intake of infants and young children and utilizes rigorous study design and state-of-the-art 24-h dietary recall methodology.